typedef struct link_element{
	char data;
	int cn;
	int ln;
	struct link_element *next;
	struct link_element *prev;
}ELEMENT;

typedef struct list_element{
	struct link_element *head;
}LIST;

ELEMENT *create_list(LIST *list){
	ELEMENT *n_ele = (ELEMENT *)malloc(sizeof(ELEMENT));
	if(n_ele == NULL)
		return(NULL);
	n_ele->data = '\0';
	n_ele->next = NULL;
	n_ele->prev = NULL;
	list->head = n_ele;
	return(n_ele);
}

ELEMENT *insert_after(ELEMENT *head, char data){
	ELEMENT *n_ele = (ELEMENT *)malloc(sizeof(ELEMENT));
	ELEMENT *tmp;
	if(n_ele == NULL)
		return(NULL);
	tmp = head->next;
	head->next = n_ele;
	n_ele->prev = head;
	n_ele->next = tmp;
	n_ele->data = data;
	return(n_ele);
}
